1. Field of the Invention
The present invention relates to a system and method for supporting inter-NAT-domain (inter network address translation domain) handoff in a VPN (virtual private network) by associating L2TP (layer 2 tunneling protocol) and mobile IP (internet protocol), which can support connective handoff over NAT gateway in a VPN.
2. Description of Related Art
In recent years, mobile communication systems tend to apply mobile IP for integrating various accessing media, such as wireless LAN, GPRS, WCDMA/cdma2000 and the like. However, for further securing various accessing media used by the users, it needs a security mechanism to protect the right of accessing a network. VPN applications also tend to access a home network, namely, Intranet sources, via a multi-tier network structure at anytime. For this requirement, it is desired to associate mobile IP and VPN to provide a user with secure and connective handoff.